Study On The Theory And Application Of The Temporal Deformation Field Measurement Technology

When the Speckle Interferometry or the Electronic Speckle Pattern Interferometry (ESPI) is applied to measure the continuous movement or deformation of an object, a temporal speckle interference field will occur. We can obtain the sequence of speckle interferograms by continuously recording the temporal speckle interference field caused by the object temporal deforming using the imaging system. In this paper, we analyzed the modulation of the interference intensity of each pixel on the time sequence speckle patterns in the time domain and proposed a new phase retrieve method, Time Sequence Phase Method (TSPM), in which the time sequence speckle interferograms are used to obtain the whole field deformation of the object. In this new method, the conventional ESPI system can be used to obtain the high quantitative phase results without using the phase shifting or the carrier device.In the Temporal Speckle Pattern Interferometry (TSPI), the possible calculation errors, which may occur in the practical application, are discussed, and some methods used to reduce the errors are given. In addition, the system parameters in the experiment are discussed and their selection principle is also presented.A lot of engineering applications are carried out using our proposed method in this paper, such as thermal deformation measurement of a car lamp, analysis of the super low frequency harmonic vibration of a piezoelectric ceramic, dynamic mechanical behavior analysis of the ballistite material and so on. It is the first time to use the conventional ESPI system (neither phase shifting nor carrier is used) to continuously analyze the super low frequency vibration with high quantitative in the world. So it is initiative and instructive for the future application of the temporal interferometry on the analysis of the vibration. In the study of the dynamic mechanical behavior of the ballistite material, the material's creep curves and the creep velocity curves are successfully obtained using TSPM, and whole field displacement distributionsof the thermal deformation and the mechanical-thermal creep at various times are also retrieved. It is the first time to introduce TSPI into the study of the material creep behaviors in the world. Such research will provide a powerful tool for the study of the material mechanical behaviors and establish the theoretical and the experimental platform for the farther research in this field.Finally, the author developed an image capture and processing software system based on the TSPM. In this software package, the multi-mode image capture methods and the time sequence phase retrieve method are integrated together.